Does anyone know of a function that will allow me to extract the positions
of the first elements of runs of similar elements within a list. For
example, suppose that
list={7,9,1,6,8,1,1,6,5,1,1,1,8,7,6,1,1,1,1,7}
I need a function that will return
{3,6,10,16}
corresponding to the runs {1},{1,1},{1,1,1},{1,1,1,1} within list
Many thanks
Tony